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[TowerTalk] MA5V Vertical question

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Subject: [TowerTalk] MA5V Vertical question
From: (Joe Reisert)
Date: Thu Jan 30 11:54:26 2003
Paul and Jim,

The Cushcraft MA5V was designed by K1BQT, Rick Littlefield and he calls it 
an "Off Center Fed Dipole). In the Jan/Feb 2002 issue of QEX, page 54, is a 
complete technical write up on same.

I believe the coax in the isolator is RG58 (not RG59). Beware, this is a 
low power antenna and is only specified to handle 250 Watts PEP SSB!


Joe, W1JR

At 07:35 PM 1/28/2003 -0700, Jim Harris wrote:
>I put up the same antenna about a month ago.  The hardware on mine was in 
>fine problems at all.  The balun is just as you mentioned 
>imho.  The radials in my estimation are too small and the balun is to keep 
>RF from coming back down the coax shield.  Looks to me like the coax for 
>the balun was of okay quality.
>The big problem I had was that the band width on 20 & 12 meters is skewed 
>towards towards the lower part of the band and there are no adjustment 
>procedures.  Have to use a tuner on the upper part of the band.  Looks 
>like just shorten the studs on the ends of the coils to raise the center 
>of the bandwidth.  Not a clue anywhere as to how much to shorten 
>them.  Know where I can get a mfj-259 cheap.  Hi!
>It does play a bit better than a carolina windom I've had up a 
>while....and, seem liek it does DX much better.
> wrote:
>>I recently put up a Cushcraft MA5V vertical for HF satellite work.  The 
>>antenna is working ok- but since I can not find a human to speak to at 
>>Cushcraft, or anyone there to return emails, I have a question about the 
>>antenna design that maybe someone here can answer.  If you look at a 
>>photo of the antenna, you'll notice a very large coaxial balun at the 
>>bottom of the antenna PVC support.  The PVC isolates the antenna which 
>>sits about about 4 feet above the balun feedpoint, and the balun is at 
>>the bottom of the PVC support- - The balun form is about 2 3/8  inches in 
>>diameter, 10 1/2 inches long,  and it takes about 30 feet of RG59 coax 
>>twisted around the form to create the balun.......what's with this 
>>monster balun??  What is it doing??
>>I've never seen anything like it before- MY guess is that it is overkill 
>>to keep RF off the feed line- ???  Any thoughts on this?
>>BTW, the QC at Cushcraft is awful...I had to redrill, rebuild, and modify 
>>a lot of missing and/or misized parts- Blah!  And the enclosed RG59 to 
>>form the balun is rat shack  junk- But the antenna is working 
>>FB!  Seriously, it's working well above expectations-
>>73  Paul  N0AH
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